Development of [111In]-DTPA-buserelin for GnRH receptor studies

Abstract

Buserelin was successively labeled with [ 111 In]-Indium chloride after residuation with DTPA-dianhydride. Radio-chromatography showed an overall radiochemical purity of >90% (RTLC) and > 95% (HPLC) at optimized conditions after labeling (specific activity: 400-450 GBq/M). The serum stability of the tracer was determined up to 24 h. The biodistribution of the tracer was determined in normal rats showing significant breast and ovaries uptakes 60 min post injection. MCF-7 cell binding of the tracer was > 98%. A significant testes uptake was demonstrated in normal male rats using SPECT studies.

Assessment of the effective absorbed dose of 4-benzyl-1-(3-[125I]-iodobenzylsulfonyl)piperidine in humans on the basis of biodistribution data of rats

“…where A tissue is the activity of 125 I in each tissue and A total is the total activity of 125 I injected into the rat [19,26]. At each time the amount of injected activity per gram of each tissue was averaged.…”

Estimated human absorbed dose for 68Ga-ECC based on mice data: comparison with 67Ga-ECC

“…where A Tissue is the 67 Ga/ 68 Ga activity in the sample, M Tissue is the mass of the sample and A Total is the total activity of 67 Ga/ 68 Ga injected into the mice [31,32]. The cumulated activity in the source organs,Ã h can be calculated by the Eq.…”

Comparison of estimated human effective dose of 67Ga- and 99mTc-labeled bombesin based on distribution data in mice

“…where A tissue (t) is the 99m Tc activity in the sample, M tissue is the mass of the sample and A total is the total activity of 99m Tc injected into the mouse [24,29,30].…”